<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>定时器setInterval</title>
</head>
<body>
    <script>
        // 语法规范 window.setInterval(调用函数，间隔时间)
        setInterval(function() {
            console.log('123');
        },1000)
        // 间隔几秒重复调用
    </script>
</body>
</html>